Hydraulic stretcher system capable of automatically detecting axial force

Abstract

The hydraulic stretcher system comprises a high-pressure oil pump, a pressure gauge, a stretching body and a high-pressure hose, the stretching body comprises a stretching nut, a through hole connected with a bolt is formed in the stretching nut, an ultrasonic probe is arranged in the through hole, and the ultrasonic probe is provided with an ultrasonic bolt axial force detection device in a matched mode. The hydraulic tensioner is provided with a central control device in a matched mode. According to the hydraulic stretcher system capable of automatically detecting the axial force, the ultrasonic probe is arranged in the stretching nut and is matched with the ultrasonic bolt axial force detection device and the central control device, so that the value of the axial force applied to the bolt is detected and controlled in real time, and the ultrasonic probe is installed through the spring device; and the high-pressure oil pump is accurately controlled through the valve, so that the output oil pressure is more accurate, hydraulic stretchers with different sizes can be arranged according to bolts with different requirements, the use limitation is reduced, and the use range of the hydraulic stretchers is wide.

Description

A hydraulic tensioner system capable of self-detecting axial force Technical Field

[0001] This utility model relates to the field of hydraulic tensioners, and in particular to a hydraulic tensioner system capable of self-detecting axial force. Background Technology

[0002] A hydraulic tensioner is a specialized tool that uses hydraulic power to provide high-precision axial tensile force for the pre-tightening and loosening of large-diameter bolts. Its core principle involves using an ultra-high-pressure pump to drive a hydraulic cylinder to apply axial tension to the bolt, causing it to elongate controllably within its elastic deformation zone. Tightening or loosening is then achieved by rotating the nut.

[0003] Because it achieves tightening control by directly tensioning the bolts, it is particularly suitable for confined spaces, heavy-duty vibrating machinery, and high-precision assembly scenarios. The hydraulic tensioner can output tensile force of several thousand kilonewtons, not only eliminating frictional errors caused by the traditional torque method but also enabling simultaneous pre-tightening of multiple bolts, significantly improving assembly quality and safety.

[0004] During construction, there are often quantitative control requirements for the tightness of bolts. The high-pressure pump station driving the hydraulic tensioner can generally only set the working oil pressure, and cannot set and control the accurate axial force value.

[0005] The ultrasonic bolt axial force testing device is a precision instrument based on the acoustoelastic theory, which indirectly calculates axial stress by measuring the change in the propagation time of ultrasonic waves in the bolt. Compared with the traditional torque method, its advantages are that it does not damage the bolt, can monitor in real time, and is suitable for bolt installation verification and in-service monitoring in aerospace, wind power, nuclear power and other fields. Summary of the Invention

[0006] The purpose of this invention is to construct a hydraulic tensioner system that can self-detect axial force, based on the existing hydraulic tensioner and the need to detect and control the axial force of bolts.

[0007] A hydraulic tensioner system capable of self-detecting axial force includes a high-pressure oil pump providing power, a pressure gauge for detecting the output pressure of the high-pressure oil pump, a tensioning body for tensioning a bolt, and a high-pressure hose connecting the high-pressure oil pump and the tensioning body. The tensioning body includes a tension nut with a through hole for connecting to the bolt. An ultrasonic probe for emitting and receiving ultrasonic signals to the bolt is located within the through hole. The ultrasonic probe is equipped with an ultrasonic bolt axial force detection device for analyzing the ultrasonic echo signal and calculating the real-time axial tensile force. The hydraulic tensioner is equipped with a central control device that receives the detected axial tensile force and controls the output pressure of the high-pressure oil pump.

[0008] Furthermore, the through hole of the tension nut is provided with an elastic device that allows the ultrasonic probe to fit against the upper end face of the bolt to be tensioned. The elastic device consists of a spring, a spring upper cover, and a spring lower cover. The spring upper cover is a ring structure and is fixedly connected to the inner wall of the tension nut. The spring lower cover is a ring structure and is connected to the spring upper cover through the spring. The spring lower cover is sleeved on the outer peripheral surface of the ultrasonic probe and fixedly connected to it.

[0009] Furthermore, guide members are fixedly installed at the positions where the spring is installed on the upper and lower spring covers, and the upper and lower ends of the spring are respectively limited by the guide members on the upper spring cover and the guide members on the lower spring cover.

[0010] Furthermore, the tensioning body includes a piston cylinder, a piston, a base, a tensioning nut, and a locking nut. The piston cylinder is fixedly connected to the base and is disposed above the base. The piston is slidably disposed within the piston cylinder. The tensioning nut passes through the middle of the piston and extends into the base. The locking nut is threadedly connected to the tensioning nut and is disposed above the piston.

[0011] Furthermore, the base is configured as a hollow structure, and the vertical wall of the base is provided with a through hole that connects the inside and outside. A gearbox assembly and a transmission gear are installed on the base. The gearbox assembly is installed on the outer wall of the base, and the transmission gear is located inside the base and driven by the gearbox assembly. The gear in the gearbox assembly meshes with the transmission gear at the through hole. The rotation center of the transmission gear coincides with the center of the base. The inner diameter of the transmission gear is configured as a dodecagonal hole that can be locked with the nut of the bolt to be stretched.

[0012] Furthermore, the piston cylinder includes an upper piston cylinder and a lower piston cylinder, and the piston includes an upper piston and a lower piston. The lower piston cylinder is fixedly connected to the base through a connecting sleeve, which is disposed on one side of the inner wall of the lower piston cylinder and the base. The upper piston cylinder is fixedly disposed on the lower piston cylinder by threads. The upper piston is slidably disposed in the upper piston cylinder, and the lower piston is slidably disposed in the lower piston cylinder. The lower end face of the upper piston abuts against the upper end face of the lower piston.

[0013] Furthermore, connecting blocks are fixedly installed on the side walls of the upper piston cylinder and the lower piston cylinder. The connecting blocks have oil passages that are connected to the oil passages in the upper piston cylinder and the lower piston cylinder. The connecting blocks also have quick connectors that are connected to the high-pressure hose.

[0014] Furthermore, a top cover is provided above the upper piston cylinder and connected to it by threads, a locking nut is pressed against the upper piston, and a disc spring is provided between the top cover and the locking nut.

[0015] Furthermore, a swivel ring for easy carrying is fixedly installed on the side wall of the top cover.

[0016] Furthermore, the ultrasonic probe is provided with a probe connection line connected thereto, and the ultrasonic probe is connected to the first end of the probe connection line, while the second end of the probe connection line passes through the tension nut and is connected to the ultrasonic bolt axial force detection device.

[0017] Furthermore, the valve of the high-pressure oil pump is equipped with a motor capable of precisely controlling the valve opening angle. The beneficial effects of this invention are as follows:

[0018] 1. By placing the ultrasonic probe inside the tension nut and using it in conjunction with an ultrasonic bolt axial force detection device, the axial force applied to the bolt can be detected in real time during the use of the hydraulic tensioner.

[0019] 2. The ultrasonic probe is installed by a spring device. The spring is fixed by the upper and lower spring covers and guided by the guide. At the same time, the ultrasonic probe is fixedly connected to the lower spring cover, so that the ultrasonic probe can only move in the vertical direction. This ensures that the upper end face of the bolt is always in close contact with the ultrasonic probe, thereby stably acquiring ultrasonic echo signals.

[0020] 3. The high-pressure oil pump is precisely controlled by valves, making the output oil pressure of the high-pressure oil pump more accurate;

[0021] 4. The central control device can process the collected ultrasonic data in real time and display it in the form of images, and control the hydraulic tensioner to work according to the preset target, thereby realizing real-time self-detection and control during the operation of the hydraulic tensioner.

[0022] 5. Different sizes of hydraulic tensioners can be set for bolts with different needs, reducing limitations in use and making it widely applicable.

[0023] The above description is merely an overview of the technical solution of this utility model. In order to better understand the technical means of this utility model and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 is a schematic diagram of the overall structure of a specific example of the hydraulic tensioner in the hydraulic tensioner system of this utility model.

[0026] Figure 2 is a schematic diagram of the internal structure of Figure 1;

[0027] Figure 3 is a magnified view of a portion of the structure in Figure 2;

[0028] Figure 4 is a magnified view of a portion of the structure in Figure 2;

[0029] In the diagram: 101. Base; 102. Gearbox assembly; 103. Transmission gear; 104. Tension nut; 105. Lower spring cover; 106. Ultrasonic probe; 107. Connecting sleeve; 108. Spring; 109. Protective sleeve; 110. Upper spring cover; 111. Connecting block; 112. Lower piston cylinder; 113. Lower piston; 114. Quick connector; 115. Upper piston cylinder; 116. Plug; 117. Upper piston; 118. Locking nut; 119. Disc spring; 120. Rotary ring; 121. Top cover; 122. Probe connection cable. Detailed Implementation

[0030] To make the technical problems solved, technical solutions, and beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0031] The hydraulic tensioner system of this utility model, which can self-detect axial force, will be further described with reference to the accompanying drawings.

[0032] The hydraulic tensioner system described in this embodiment includes a high-pressure oil pump providing power, a tensioning body for tensioning bolts, an ultrasonic probe for emitting and receiving ultrasonic signals to the bolts, an ultrasonic bolt axial force detection device for analyzing ultrasonic echo signals and calculating real-time axial tensile force, and a central control device for receiving the detected axial tensile force and controlling the output pressure value of the high-pressure oil pump. The high-pressure oil pump is connected to the tensioning body via a high-pressure hose, and is equipped with a pressure gauge capable of detecting the output pressure value of the high-pressure oil pump. The valve of the high-pressure oil pump is equipped with a motor capable of precisely controlling the valve opening angle.

[0033] As shown in Figures 1 and 2, the tensioning body includes a base 101, which is a hollow structure. The vertical wall of the base 101 has a through hole that connects the inside and outside. A gearbox assembly 102 is installed on the outer wall of the base 101. A transmission gear 103 is provided inside the base 101. The teeth of the transmission gear 103 mesh with the teeth of the gear in the gearbox assembly 102. The transmission gear 103 is driven by the gearbox assembly 102. The rotation center of the transmission gear 103 coincides with the center of the base 101. The transmission gear 103 has an inner diameter that is set to be a dodecagonal hole that can be locked with the nut of the bolt to be tensioned.

[0034] A lower piston cylinder 112 is fixedly installed above the base 101. The lower piston cylinder 112 is fixedly connected to the base 101 through a connecting sleeve 107. The lower piston cylinder 112 is a hollow structure. The connecting sleeve 107 is located on the inner side wall of the lower piston cylinder 112 and the base 101. A lower piston 113 is slidably connected to the lower piston cylinder 112. The lower piston 113 is a hollow structure. A protective sleeve 109 is installed on the inner side of the lower piston cylinder 112 and fixed to it by bolts. The protective sleeve 109 extends downward into the base 101.

[0035] Protective sleeve 109 is used to protect the tension nut and reduce sliding wear.

[0036] An upper piston cylinder 115 is installed above the lower piston cylinder 112 and is fixedly connected to it by threads. The upper piston cylinder 115 is a hollow structure. An upper piston 117 is slidably connected to the upper piston cylinder 115. The upper piston 117 is a hollow structure. The lower end face of the upper piston 117 presses against the upper end face of the lower piston 113.

[0037] A connecting block 111 is fixedly installed on the outer side wall of the lower piston cylinder 112 and the upper piston cylinder 115. The connecting block 111 is provided with a plug 116 for sealing the connecting block and a quick connector 114 for connecting to the high pressure hose.

[0038] The connecting block 111 is equipped with an oil passage, which includes a main branch and branches. The main branch of the oil passage is connected to the quick connector 114. The first branch of the oil passage is connected to the oil passage provided in the upper piston cylinder 115, and the second branch of the oil passage is connected to the oil passage provided in the lower piston cylinder 112.

[0039] As shown in Figure 4, a top cover 121 is installed above the upper piston cylinder 115 and is fixedly connected to it by threads. The top cover 121 has an annular structure. A locking nut 118 is pressed against the upper piston 117. The locking nut 118 has a hollow structure. A disc spring 119 is provided between the top cover 121 and the locking nut 118. A portable rotating ring 120 is fixedly installed on the side wall of the disc spring 119.

[0040] As shown in Figures 2 and 3, the locking nut 118 is provided with a tension nut 104 connected to it by threads. The tension nut 104 extends downward and passes through the upper piston 117 and the lower piston 113 in sequence, and then extends into the base 101. The tension nut 104 is protected by the protective sleeve 109 to reduce wear.

[0041] The tension nut 104 has a through hole for connection with a bolt. The through hole includes a first section and a second section, with the diameter of the first section being smaller than that of the second section. The upper part of the first section has a flower-shaped groove for mates with a quick-release wrench. A spring cover 110 is fixedly installed on the top of the second section. The spring cover 110 has an annular structure. Two guide members are fixedly installed on the lower end face of the spring cover 110. The guide members are cylindrical. A spring 108 is fixedly installed inside the tubular guide members. The spring 108 extends downward, and a spring cover 105 is fixedly installed at the lower end of the spring 108. The spring cover 105 has an annular structure. Two guide members are fixedly installed on the upper end face of the spring cover 105. The guide members are cylindrical. The lower end of the spring 108 is fixedly connected to the tubular interior of the guide members. The spring 108 is always in a vertical state.

[0042] An ultrasonic probe 106 is fixedly installed on the inner wall of the spring cover 105. A probe connection cable 122 is fixedly installed above the ultrasonic probe 106 and connected to it. The first end of the probe connection cable 122 is connected to the ultrasonic probe 106, and the second end of the probe connection cable 122 passes through the tension nut 104 and is connected to the ultrasonic bolt axial force detection device. The ultrasonic bolt axial force detection device is connected to the central control device via Ethernet. The central control device is connected to the motor via wires. The output end of the motor is embedded with the valve of the high-pressure oil pump, so that the valve rotates with the rotation of the motor.

[0043] The working principle and process of the hydraulic tensioner system described in this embodiment are as follows:

[0044] (1) Before starting the stretching, the equipment and connecting parts need to be inspected to ensure that the hydraulic system, tensioner and bolts are in good condition. Check whether each part in the hydraulic tensioner is intact and confirm that there is no leakage or damage. Apply coupling agent to the bottom surface of the bolt to be stretched, align the tensioning body with the bolt, and ensure that the threads of the tensioning nut 104 match the threads of the bolt to be stretched.

[0045] (2) Insert the special quick wrench into the flower-shaped groove above the tension nut 104, rotate the quick wrench to drive the tension nut 104 and the bolt to be tested to tighten gradually. During the tightening process, the compression of the left and right springs makes the ultrasonic probe 106 fit tightly against the surface of the bolt to be stretched. At the same time, as the overall height of the tension body decreases, the nut of the tension bolt will be inserted into the dodecagonal hole in the center of the transmission gear.

[0046] (3) Connect the high pressure oil pipe of the high pressure oil pump to the connecting block, and supply high pressure oil to the upper piston cylinder 115 and the lower piston cylinder 112 synchronously. Set the target axial force to be applied to the bolt on the central control device, and start rotating by controlling the motor. The motor drives the valve of the high pressure oil pump to rotate at a constant angular velocity. The high pressure oil pump outputs hydraulic pressure related to the valve opening to the tension body. The hydraulic oil enters the upper piston cylinder 115 and the lower piston cylinder 112 through the connecting block, driving the upper piston 117 and the lower piston 113 to move. As the hydraulic pressure increases, the upper piston 117 and the lower piston 113 move upward, pushing the locking nut 118, and applying tension to the tension nut 104 through the locking nut 118, so that the tension nut 104 drives the bolt to extend axially.

[0047] (4) The ultrasonic probe 106 emits and receives ultrasonic signals at a constant period (the period can be set) and transmits them through the probe connection line. After analyzing the ultrasonic echo signal, the ultrasonic bolt axial force detection device uploads the real-time bolt axial force information to the central control device and displays it.

[0048] (5) The central control device determines whether the motor needs to continue to be driven by comparing the real-time axial force with the target axial force;

[0049] (6) When the real-time signal reaches the required axial force, the central control device controls the motor to stop rotating, maintains the opening of the high-pressure oil pump valve, and keeps the tensile force constant. At this time, by rotating the knob above the gearbox assembly 102 with a wrench, the transmission gear 103 is controlled to drive the nut of the bolt to be stretched to rotate through the internal gear transmission, so that the nut fits with the flange.

[0050] (7) The central control device drives the motor to reverse, thereby closing the valve of the high-pressure oil pump. Under the action of the internal disc spring, the base, upper and lower piston cylinders and top cover and other components of the tension body move upward until they return to the initial state. At the same time, the hydraulic oil flows back to the high-pressure oil pump under the internal compression.

[0051] (8) After the pressure is released, the axial force is tested again to ensure that the axial force of the bolt meets the requirements.

[0052] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A hydraulic tensioner system capable of self-detecting axial force, comprising a high-pressure oil pump providing power, a pressure gauge for detecting the output pressure value of the high-pressure oil pump, a tensioning body for tensioning bolts, and a high-pressure hose connecting the high-pressure oil pump and the tensioning body, characterized in that, The tensioning body includes a tension nut, which has a through hole for connecting to a bolt. An ultrasonic probe for emitting and receiving ultrasonic signals to the bolt is provided in the through hole. The ultrasonic probe is equipped with an ultrasonic bolt axial force detection device for analyzing ultrasonic echo signals and calculating real-time axial tensile force. The hydraulic tensioner is equipped with a central control device for receiving the detected axial tensile force and controlling the output pressure value of the high-pressure oil pump.

2. The hydraulic tensioner system capable of self-detecting axial force according to claim 1, characterized in that, The tension nut has an elastic device in its through hole that allows the ultrasonic probe to fit against the upper end face of the bolt to be tensioned. The elastic device consists of a spring, a spring top cover, and a spring bottom cover. The spring top cover is an annular structure and is fixedly connected to the inner wall of the tension nut. The spring bottom cover is an annular structure and is connected to the spring top cover through the spring. The spring bottom cover is sleeved on the outer circumferential surface of the ultrasonic probe and is fixedly connected to it.

3. The hydraulic tensioner system capable of self-detecting axial force according to claim 2, characterized in that, Guide members are fixedly installed at the positions where the spring is installed on the upper and lower covers of the spring. The upper and lower ends of the spring are respectively limited by the guide members on the upper cover and the lower cover of the spring.

4. The hydraulic tensioner system capable of self-detecting axial force according to claim 1, characterized in that, The tensioning body includes a piston cylinder, a piston, a base, a tension nut, and a locking nut. The piston cylinder is fixedly connected to the base and is located above the base. The piston is slidably disposed within the piston cylinder. The tension nut passes through the middle of the piston and extends into the base. The locking nut is threadedly connected to the tension nut and is located above the piston.

5. The hydraulic tensioner system capable of self-detecting axial force according to claim 4, characterized in that, The base is a hollow structure with a through hole on its upright wall to connect the inside and outside. A gearbox assembly and a transmission gear are mounted on the base. The gearbox assembly is mounted on the outer wall of the base, and the transmission gear is located inside the base and driven by the gearbox assembly. The gears in the gearbox assembly mesh with the transmission gear at the through hole. The rotation center of the transmission gear coincides with the center of the base. The inner diameter of the transmission gear is set as a dodecagonal hole that can be locked with the nut of the bolt to be stretched.

6. The hydraulic stretcher system of claim 4, wherein, The piston cylinder includes an upper piston cylinder and a lower piston cylinder. The piston includes an upper piston and a lower piston. The lower piston cylinder is fixedly connected to the base by a connecting sleeve. The connecting sleeve is disposed on one side of the inner wall of the lower piston cylinder and the base. The upper piston cylinder is fixedly disposed on the lower piston cylinder by threads. The upper piston is slidably disposed in the upper piston cylinder. The lower piston is slidably disposed in the lower piston cylinder. The lower end face of the upper piston abuts against the upper end face of the lower piston.

7. The hydraulic stretcher system of claim 6, wherein, Connecting blocks are fixedly installed on the side walls of the upper piston cylinder and the lower piston cylinder. The connecting blocks have oil passages that are connected to the oil passages in the upper piston cylinder and the lower piston cylinder. The connecting blocks are also equipped with quick connectors that are connected to the high-pressure hose.

8. The hydraulic tensioner system capable of self-detecting axial force according to claim 6, characterized in that, The upper piston cylinder is provided with a top cover connected to it by threads. The locking nut is pressed against the upper piston. A disc spring is provided between the top cover and the locking nut. A swivel ring for easy carrying is fixedly installed on the side wall of the top cover.

9. The hydraulic tensioner system capable of self-detecting axial force according to claim 4, characterized in that, The ultrasonic probe is provided with a probe connection line connected to it, and the ultrasonic probe is connected to the first end of the probe connection line. The second end of the probe connection line passes through the tension nut and is connected to the ultrasonic bolt axial force detection device.

10. The hydraulic tensioner system capable of self-detecting axial force according to claim 1, characterized in that, The valve of the high-pressure oil pump is equipped with a motor that can precisely control the valve opening angle.

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